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Planar solid oxide fuel cells (SOFC) with CuO/gadolinium‐doped ceria (GDC) supporting anode were produced and tested in H2and in CH4/CO2mixture at 650 °C. The electrolyte densification at 900 °C was promoted by compressive strains induced by larger anodic thickness. The reduction behaviour of CuO/GDC anodic powders was preliminarily evaluated. The electrochemical measurements showed an increasing power density with the anode thickness (from ≈500 μm to ≈1.4 mm) reaching a maximum value of 227 mW cm−2at 650 °C in pure H2. Power density of 29 mW cm−2was measured in wet CH4/CO2biogas mixture at 650 °C. Catalytic activity measurements towards methane dry reforming showed limited conversion at all investigated temperatures, this suggesting that the actual anodic reaction is the methane combustion. Scanning electron microscope observations and energy dispersive X‐ray analyses of the cell tested in CH4/CO2mixture did not show any carbon deposit, thus pointing out that the Cu/GDC cermet can be considered a stable and reliable anodic substrate for IT‐SOFC fed by CH4/CO2mixture. Cosintering: Planar CuO/GDC based IT‐SOFCs are produced with different anodic thickness and a full dense electrolyte can be achieved at 900 °C. This is due to the compressive stresses induced by an optimised anodic thickness on the electrolyte layer upon sintering. Optimised cell produces power outputs in H2or in CH4/CO2anodic fuels.

Solid Oxide Cell electrode engineering is of paramount importance to obtain high performing, versatile and reliable devices. In this work, the structural and morphological evolution of Sr2FeNi0.4Mo0.6O6-δ(SFNM) is investigated and fully characterized over subsequent temperature programmed reductions. Comparison of the results of X-ray diffraction, high transmission electron microscopy and electrochemical impedance spectroscopy analyses confirms how metallic phase exsolution upon reduction endows the perovskite with highly active Ni-Fe-based catalytic sites for applications in hydrogen-fueled SOFCs. As a novelty, this study presents voltage-induced reduction of SFNM at 1.6 V as a fast and reliable way to induce morphological and structural changes of the SFMN-derivate exsolved-perovskite. This enhances its catalytic activity towards CO2electrolysis in SOEC configuration, providing SFNM with a high versatility in solid oxide cells applications.

Intermediate temperature solid oxide fuel cells (IT‐SOFCs) were fabricated depositing proton conducting BaCe0.9Y0.1O3–x(BCY10) thick films on cermet substrates made of nickel oxide–yttrium doped barium cerate (NiO–BCY10) using electrophoretic deposition (EPD) technique. The influence of the EPD parameters on the microstructure and electrical properties of BCY10 thick films was investigated. Deposited BCY10 thick films together with green anode substrates were co‐sintered in a single heating treatment at 1,550 °C for 2 h to obtain dense electrolyte and suitably porous anodes. The half‐cells were characterised by field emission scanning electron microscopy (FE‐SEM) and by X‐ray diffraction (XRD) analysis. A composite cathode specifically developed for BCY electrolytes, made of La0.8Sr0.2Co0.8Fe0.2O3(LSCF, mixed oxygen‐ion/electronic conductor) and BaCe0.9Yb0.1O3–δ(10YbBC, mixed protonic/electronic conductor), was used. Fuel cells were prepared by slurry coating the composite cathode on the co‐sintered half‐cells. Fuel cell tests and electrochemical impedance spectroscopy (EIS) were performed in the 550–700 °C temperature range. A maximum power density of 296 mW cm–2was achieved at 700 °C for electrolyte deposited at 60 V for 1 min.

BaZr0.8Y0.2O3–δ, (BZY), a protonic conductor candidate as an electrolyte for intermediate temperature (500–700 °C) solid oxide fuel cells (IT‐SOFCs), was prepared using a sol–gel technique to control stoichiometry and microstructural properties. Several synthetic parameters were investigated: the metal cation precursors were dissolved in two solvents (water and ethylene glycol), and different molar ratios of citric acid with respect to the total metal content were used. A single phase was obtained at a temperature as low as 1,100 °C. The powders were sintered between 1,450 and 1,600 °C. The phase composition of the resulting specimens was investigated using X‐ray diffraction (XRD) analysis. Microstructural characterisation was performed using field emission scanning electron microscopy (FE‐SEM). Chemical stability of the BZY oxide was evaluated upon exposure to CO2for 3 h at 900 °C, and BZY showed no degradation in the testing conditions. Fuel cell polarisation curves on symmetric Pt/BZY/Pt cells of different thicknesses were measured at 500–700 °C. Improvements in the electrochemical performance were obtained using alternative materials for electrodes, such as NiO‐BZY cermet and LSCF (La0.8Sr0.2Co0.8Fe0.2O3), and reducing the thickness of the BZY electrolyte, reaching a maximum value of power density of 7.0 mW cm–2at 700 °C.

We report on the electrical properties of a hybrid organic/inorganic material synthesized by a sol-gel technique. Spin-coated films with sputtered Nb electrodes in a sandwich-type geometry were studied by a.c. measurements. The aging of the films affected the resistance of the samples. Electrochemical impedance spectroscopy (EIS) measurements were performed in a test chamber at different relative humidity (RH) values to evaluate the aging mechanism.

Sol-gel derived composite materials were prepared with nano-sized copper particles in silica matrix. Nano-sized oxide coatings were grown on the nano-particles of copper by subjecting the composites to a controlled oxidation treatment at different temperatures. The current response of samples with oxide layers of different thickness were studied at fixed temperatures in the range 350–450°C in the presence of different concentrations of CO and NO2. The nano-composites were sensitive to both the gases. The operating temperature and the oxide thickness were found to have significant effect on the sensing properties.

The direct application of corrosion inhibitors on metal surfaces is potentially dangerous for the environment and the restoration operators, thus new conservation strategies are mandatory. In this study, two copper corrosion inhibitors, 1H-benzotriazole (BTA) and 5-phenyl-1H-tetrazole (PT), are encapsulated in a silica nanocontainer, for future application in smart coatings, with the aim to reduce the amount of chemicals used in treatments, their dispersion in the environment and the direct exposure of the operators to these chemicals. In particular, composite silica nanocapsules, containing the corrosion inhibitors, are prepared via one-step synthesis, based on mini-emulsion polymerisation processes.